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As of December 2018

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If you play on Xbox it’s now on game pass! Give it a whirl it’s worth your time!

Usually, when pairs of brown trout prepare to spawn, both fish court and quiver violently with their mouths open. The female will then dig into the sediment, releasing her eggs into a wee nook, before the male comes over to release his cloud of sperm and fertilise 'em. Check it out for yourself here. Beautiful.

It's not entirely clear why she does this. Perhaps she's waiting for a more superior father - if one arrives, she'll ditch the inferior chap and go for the trout hottie. If one doesn't arrive however, she may repeat the process with the original candidate. Likewise, it's thought it might also be an insurance policy against infertility - making sure the boy isn't shooting blanks and can produce the goods before sharing her own.

Source: Originally published in Animal Behaviour in 2001, check out the scientific paper (behind paywall; or request directly from the authors here), for more information!

Ah, this makes sense. There's probably a lot more energy involved in making eggs, and the females that produced this behavior oh so long had more successful mating seasons since they didn't waste any, thus it was passed on. I think? Is that how evolution works?

Yup! Eggs are expensive, whilst sperm is dirt cheap. This cost differential explains a whole host of differences in form and behaviour between the sexes right across the animal kingdom.

Known as sexual selection, in short: 'cos they're fronting the bill, females tend to be choosy, and therefore males compete amongst each other for their choice. The few winning males pass down their attractive characteristics to the next generation, and females likewise pass on their strong desire for those attractive male traits. Hence a positive feedback loop of sexiness that results in rutting stags, elaborate peacock tails and dances by male birds of paradise, elephant seal harems, frogs that croak and crickets that chirp loudly.

A flashy car doesn't attract women. It attracts teenage boys, and older men, who will tell you about the muscle car they USED to have 40 years ago, before their wife/girlfriend/wife née girlfriend, got pregnant and made them sell it.

I know a couple girls who fell for guys wearing nice suits in a club only to realize later the guys only owned one nice suit, no car, no money, etc. But the nice suit made them look rich enough to be desirable, and they got laid.

The few winning males pass down their attractive characteristics to the next generation, and females likewise pass on their strong desire for those attractive male traits. Hence a positive feedback loop of sexiness

Do Brown Trout develop Jacks that will try to sneak in on a breeding pair, like many of the Pacific salmonids, to counter act choosy females?

Ooh, this piqued my curiosity too! After a lil' digging, according to this study, the answer is no. Instead of alternative mating strategies ('jacks' vs. 'hookjaws' in salmon), male trout essentially just tag-team a female - with multiple consecutive sperm releases over her egg load. In which case, males may be engaging in sperm competition, with the battle for fertilisation happening between the sperm cells themselves, not so much the adults (though they do try to fend each other off and sometimes guard females for a while post-coitus).

H-hi, beautiful trout! nervous quivering I c-c-couldn’t help but notice that you have a very nice dorsal fin OwO D-do you mind if I... big gulp of water over my gills quiver violently over your eggs in that sediment over there?!? looks hopeful
...
No? Well FUCK YOU, YOU SLUTTY SALMON LOL YOURE OF INFERIOR BREEDING STOCK ANYWAY! Have fun breeding with Chadfish, who will just use you for your eggs and then swim upstream quivers violently with mouth open, ejaculating into the water around you and runs away laughing

Ah, good question! She half buries the eggs to prevent 'em being flushed downstream, and also to offer a little extra protection against the odd marauding predator. They only lay their eggs in loose gravel beds with little silt for this reason; gravel doesn't smother them completely, so there's still plenty of water flow when buried to provide oxygen that helps them develop.

Smh even the trout ladies cant handle nice guys, he did everything right and what, just because he's judged poorly he doesnt get to reproduce? Even fucking trout are into god damn chads, I hate this existance man, so unfair to nice guys just wanting to breed. /s

Until now I didn't realize that I have no idea how fish sex works. Does the male just swim around and when she lays her eggs he just fires on them? Do they even have physical contact or is it like hands free masturbation for both?

On the opposite side of the animal kingdom when it comes to apes - chimps, orangutans, and gorillas will kill the infant of the female to make the female fertile again and while she is grieving will basically rape her to impregnate her with his offspring.

Heavily edited information and conclusions - these anthropomorphizing stories of animals and their motives are always oversimplified and seldom accurate. The real story is more likely that there are many other factors that play into this behavior, and/or that observers are not quite sure what is causing it and are just speculating that these are the reasons. What actually may be happening is most likely not even close to what this article is trying to paint it as.

Found this comment depressingly low down. Is laying the eggs even related to "an orgasm"? The title is crazy clickbaity. Guess people would rather glance at the title, comment "doesn't matter had sex" and run off to the next sexy title.